2006/03/31 by Man-Hong Yung, Man‐Hong Yung · 1 citation
Computer Science · Mathematics · Physics and Astronomy · #Algorithm #Classical mechanics #Computation #Computer science #Coupling constant #Hamiltonian (control theory) #Heisenberg limit #Limit (mathematics) #Mathematical analysis #Mathematical optimization #Mathematics #Physics #Quantum #Quantum Computing Algorithms and Architecture #Quantum Information and Cryptography #Quantum and electron transport phenomena #Quantum computer #Quantum mechanics #Quantum network #State (computer science) #Statistical physics #quant-ph
paper · pdf · doi:10.1103/physreva.74.030303
published as Phys. Rev. A 74, 030303(R) (2006) · 5 pages, no figure; improved version
arxiv created 2006/05/02 · openalex publication_date 2006/09/14 · arxiv updated 2009/12/01 · openalex created_date 2025/10/10 · openalex updated_date 2026/08/05
The basic idea of spin-chain engineering for perfect quantum state transfer (QST) is to find a set of coupling constants in the Hamiltonian such that a particular state initially encoded on one site will evolve freely to the opposite site without any dynamical controls. The minimal possible evolution time represents a speed limit for QST. We prove that the optimal solution is the one simulating the precession of a spin in a static magnetic field. We also argue that, at least for solid-state systems where interactions are local, it is more realistic to characterize the computation power by the couplings than the initial energy.